Condition assessment modeling for distribution systems using shared frailty analysis

摘要

Using data collected by the Laramie, Wyo., water utility, this research found that pipe diameter and pipe material were two major factors that related to pipe breakage rates. In addition, there were a number of unknown factors (frailties) that also affected breakage rates. It was determined that the frailty was much greater for metallic pipe than for PVC pipe even though the expected life of the PVC pipe was shorter.rnAs a result of this research two important conclusions can be drawn: (1) it is possible to identify the major factors that influence the reliability of a specific drinking water infrastructure, and (2) there are a number of unidentified factors that affect pipe breakage rates. This article presents models that can be used for predicting pipe break rates to calculate the cost and benefits associated with inspection technology.rnPotential insights that can be obtained by systematically organizing and analyzing a drinking water utility's infrastructure database will be of interest to utility managers. However, achieving such a level of organization is difficult and challenging, and requires dedication and commitment on the part of the utility staff.